Service Manual - BrandsMart USA
Contents
1. Sal IENT B E B a Service Manual CHEST FREEZER SUPER DESIGN Models PFR5080M This product is for domestic use only Use amp care manual Important safeguards CONTENT Siri LR Gassuenate beuoaceses Product code illumination and Series Introduction lo Telpilec ifo EP Safety precautions sssss Function Schedule erii ni System Flow ChGSIt u iiir roii EE Up oi ERE PR LOS ES CIFCUIT Didier Maintenance Service and Trouble Shooting Specifications Net capacity L Color Power Supply V Hz Rated Input Power W Power Consumption kW h 24h Net Weight kg Gross Weight kg Unit Dimension D W H mm Packing Dimension D W H mm Container Quantity 40 HQ PCS Specifications PFR5080M White 115 60 730 523 850 770 545 885 Safety precautions Safety precautions This appliance uses 115V 60Hz AC It is required to use separate dedicated for power supply outlet with securely grounding Failure in eoperaticr and damage 10 1he corral panel Th power cable od his appliance is 11100 wih free core iler rre 131 Or ie compressor wall CC Cur id voltage is Lareun ding plug complying wn 1iree cecre Lareunding oudside 1He range 108 132V unless a regul dior wiih a 01181 Inne case should ihe 1hird plug pin lorcund ing capaci Of over SCA er higher is installed da2. a Feel the compressor when running its temperature should be generally less than 90 C in the normal state it may exceed 90 C in case of running for a longer period of time b After the compressor has operated normally for 5 10 minutes ouch and feel the condenser the temperature of its upper part should be higher than that of its lower part or its right part is hotter than its left part depending on the type of condenser coil this indicates that the refrigerant is circulating If the condenser is not hot this means the leakage of refrigerant In case the condenser radiates heat for only several minutes and then cools down this means that the filter and capillary have been clogged As for the forced air cooling condenser hot air will be blown out of it this means that the system is out of order c Feel the filter s temperature During the normal operation of refrigerating system the temperature on the filter s surface should be a little higher than the ambient temperature if you touch it with your hand you will have a sense of slight heat In case dew condensation appears due to the fact that its temperature is obviously lower than the 16 Maintenance Service and Trouble Shooting ambient temperature this means that most meshes of its screen has been clogged resulting in an obstructed flowing of refrigerant thus causing a drop in temperature due to throttling d Feel the temperature of exhaust gas from the refrigera
3. compressor circuit Analysis of Trouble In case the compressor cannot be started this will generally exhibit in the power supply circuit for instance power failure poor contact of switch and blown fuse Make a comprehensive analysis of these phenomena fine out its real cause and take correct measures to remove this trouble Hemedy 24 Maintenance Service and Trouble Shooting a Check the input power circuit to see whether where is voltage of the power supply namely the circuit which is connected to the knife switch This can be determined with an avometer or a test pencil If a blown fuse is found ascertain and remove its cause then replace it with a new one of the same specifications b Check the compressor accessories including its thermal protector and relay In case the thermal protector is damaged the compressor cannot be powered on If the relay is out of order the motor will not run and hum sound can be heard from it after the compressor is turned on in that case shut it down immediately otherwise the motor windings will be burned out in case this condition lasts longer c Check the relay contacts and plugs to see if they are perfect and work reliably Poor contact may cause the motor not running or humming 2 Check the circuit voltage to see whether it is normal Analysis of trouble If the circuit voltage is obviously lower than its rated value it will be difficult to start the motor and a hum sound can be
4. e poner cable he Cui Cr rered Do not damage power cable Incase of damaged power cable Be sure no 10 pull Qui ihe plug dl 1e appliance by When 11e power cable or plug has beer wor iiis drawang ihe power cable Ee sure 10 direc ily pull Gui 11 prenibited 10 Continue 18 use n In 1s Case mnis required da e ciuda by tiny grasping ihe plug replace 1 by Tactiarv guihtrized service shop Dondi cause ihe appliance body press 1He porn ar Cable nor should dy people red cr i When mening Ne appliance iron wall be caredol no 10 roll e darige power c able When there is leakage of inflammable Please pull out power plug under the gas following situations ose ie valve od leak ing aas Poll Oui power plug prior 10 clearing cr repairing Open d os and windows When replacing damaged lamp iiis required 10 pull Heither iry 10 drag nor inseri any power plug Tor Oui power plug 10 pre ven electrical Snack any electrical unit Such as redriger aicr e Safety precautions It is absolutely prohb ited to putinside the Do rotkeep medicine vaccine or chemical appliance hazardous inflammable or reagent inthe appliance This refrigerator explosive articles strong corrosive acid is for household use which cannot store alkali etc item with strict requirement for temperature Re NOM EE P EL JE DRE a DU B Do not store or use gasoline or other Do notplace any electrical plugs regulators flammable article in th
5. from the compressor or the temperature of its causing is too high Cut the discharge port open and operate the compressor feel it if there is pressure at the discharge port with your finger For a normal compressor its discharge port is difficult to be blocked with your finger if you just apply a little effort 5 Too thick frost layer formed on evaporator Analysis of Trouble If a direct cooling Freezer is to be used for a prolonged period of time be sure to defrost its evaporator regularly if you fail to do so the frost layer on the evaporator tubing will become thicker and thicker Heat conduction will be severely affected when the whole tubing is wrapped with a transparent ice layer and finally the temperature in the Freezer cannot drop down to the prescribed range Remedy Turn the Freezer off and make preparations for defrosting open the Freezer door to let the air come in or use a fan to speed up air flowing so as to shorten the time needed for defrosting Never strike the frost layer with any iron tools or wood stick in order to avoid damage to the evaporator tubing 6 Refrigerating oil left in evaporator tubing Analysis of Trouble During the process of refrigerating cycles a little refrigerating oil may remain in the evaporator tubing and after a longer time of operation if there is considerable refrigerating oil left in the evaporator the heat conduction effect will be severely affected thus causing a poor refrigera
6. gas flowing out of the crack of the pressure tube inside the compressor and clucks are the sound of striking after the suspended spring inside the compressor has broken During the normal operation of compressor a slight and uniform hum sound due to undulation of electric current can be heard generally this is a normal phenomenon However if it sounds like tong tong i e an impact sound inside the compressor this means that a large quantity of wet vapour of refrigerant or refrigerating oil has come into the compressor cylinder if it sounds like dang dang a striking sound of metal parts inside the compressor this means that some moving parts have loosened note to differentiate this sound from those formed during starting or stopping the compressor b Listen to the sound caused by the flowing of gas in the evaporator Open the Freezer door while the compressor is in operation incline your ear and listen attentively the gas flow sound inside the evaporator If it sounds like gentle whistling accompanied by a sound similar to water flowing this is the sound produced by the normal circulation of refrigerant within the evaporator In case only the gas flowing sound can be heard and there is no water flowing sound this indicates that the refrigerant has already percolated If neither the flowing sound nor the gas sounds from the evaporator can be heard this means that the filter or capillary has been clogged 3 Touch and Feel
7. heard from it Hemedy Measure the voltage with a voltmeter if it is really too low give directions to the user for buying a stabilizer so as to step up the voltage thus normal operation can be achieved 3 Check the thermal relay to see whether its contacts are closed Analysis of Trouble The contacts of thermal relay sometimes may be open due to the leakage of temperature sensing agent from the temperature sensor Hemedy Remove the relay cover to check up its contacts if they are open this means that the original setting is not properly set or temperature sensing agent has leaked out of the temperature sensor Try to turn the adjusting stem of this value in the direction of the lower temperature graduation then check the contacts to see whether they are closed If they are still not closed dismantle the temperature sensing disc and then immerse it into warm water to see whether the contacts actuate if not it can be preliminarily determine that temperature sensing agent has leaked out and it must be replaced with a new thermostat 4 Motor troubles and other electric faults a Motor windings have been burned or short circuited between turns Analysis of Trouble When motor windings have been burned or short circuited between turns the fuse will be blown repeatedly and the blowout occurs particularly at the instant when you close the knife switch Hemedy Check the terminals and the outer casing to see whether they are short ci
8. loosening of parts Improper and compact laying of tubes or the loosening of parts may cause vibration and noise 28 Maintenance Service and Trouble Shooting 4 Inspection method To find the sources of noise press the vibration spot with your hand while the Freezer is in operation and listen attentively whether the vibration becomes weake or vanishes If the Freezer has not been levelly placed put a level meter on its top table and adjust the leveling screws on its legs In case noise occurs from the compressor strike different locations on the side surface of its case using a rubber hammer or hand hammer with a wood block in between so as to determine whether the suspended springs are out of balance or being seized 29 Manual de uso y cuidado Premium Precauciones importantes ES produco s DATA NU Heus i c Nicmene
9. of trouble characteristics as well as operating conditions for various kinds of Freezers Three Essentials for Checkup 1 Look a Check the tubing of refrigerating system for cracks and various welding points for leaks if leakage occurs an oil stain can be seen definitely b Check the suction and exhaust pressure values high pressure and low pressure of compressor to see whether they are normal C Check the conditions of frost attached to its evaporator and gas return tube It is abnormal if frost has formed on part of the evaporator or there is no frost attached to it d Payattention to the speed of temperature drop inside freezer compartment It is abnormal if the speed of temperature drop is obviously slower than the corresponding normal speed e Check the environment to see whether it is suitable for placing a Freezer f Check Freezer door seal case table surface and heat insulation layer g Look at the main control board to ascertain if various indication states are normal 2 Listen a Listen to the noises produced when the compressor is running 15 Maintenance Service and Trouble Shooting Hums from a fully enclosed aggregate unit is the sound caused by overload indicating that the motor cannot be started normally meanwhile a clattering sound can be heard from inside the start relay which is produced because the start contacts cannot be released normally A whistling sound is caused by the high pressure
10. the opening and closing of gas suction valve and discharge valve to suck and discharge the refrigerant If the valve block is broken the refrigerant can not be discharged and hence no refrigerating can be achieved Method for making judgement It is quite difficult to differentiate this trouble from others because they often have similar symptoms In repairing firstly hear attentively if there is some abnormal sound coming from the compressor sometimes the broken pieces of valve block may strike against the cylinder and feel the compressor casing with your hand to ascertain whether it is too hot this is also helpful to the troubleshooting secondly measure the pressures at the high and low pressure ports of the compressor with pressure gauges if the gas suction valve block is broken the suction pressure gauge pointer will swing violently and the suction pressure is very high whereas when the gas discharge valve block is broken the discharge pressure gauge pointer will swing drastically and the discharge pressure is very high In the both cases stop the compressor at once and if technique is available open the cylinder cover and check up the valve block repair it or replace it with a new one C Sudden stop of Compressor during Its Running 22 Maintenance Service and Trouble Shooting The cause of sudden stop of a compressor during its running is mostly that the gas suction pressure and or discharge pressure exceed their resp
11. 0V power output Check all cords and power cords Check and repair compressor and accessory 13 Maintenance Service and Trouble Shooting 5 Normal Phenomena Not Troubles for Freezers In a domestic Freezer there is not only a complicated electric control system but also a refrigerating system that is difficult to discern whether it is in a good working condition Both the systems are related and affect each other If a certain part of a Freezer works abnormally Its refrigerating efficiency will decrease operation properties will become unstable or even it cannot be used normally for those serious cases Freezers are generally of larger volume once troubles appear to send them to a service department is really a tough thing if such is the case the user will always be in suspense sometimes normal phenomena will be erroneously regarded as troubles Therefore before we deal with the topics of frequently occurring troubles of Freezers and their remedies we should firstly give a brief account of some normal phenomena which are not troubles In case any one of such phenomena occurs there is no need to worry about it and the user can use it at total ease 1 When the compressor of a Freezer has just stopped running a rumbling sound can be heard from inside its evaporator This is a sound caused by the flowing of refrigerant in the evaporator tubing Because the pressure difference is still greater after the compressor ha
12. There is air left in the refrigerating system Analysis of Trouble Residual air in the refrigerating system will reduce its refrigerating efficiency The prominent phenomena are the increase in its gas suction and exhaust pressures however the gas exhaust pressure will not exceed its rated value obvious increase in temperature in the segment from the compressor outlet to the condenser inlet Because there is air in the system both the gas exhaust pressure and temperature will rise and moreover the gas flowing sound is intermittent and obviously louder Hemedy After shut down for several minutes open the tubing evacuate it and then recharge the system with refrigerant 4 Low efficiency of compressor Maintenance Service and Trouble Shooting Analysis of Trouble Low efficiency of a refrigerating compressor refers to the actual reduction of gas discharge capacity and hence the corresponding reduction of refrigerating capacity under the condition that the refrigerant in the system is unchanged This phenomenon occurs mostly when the compressor has been used for quite a long time its moving parts have worn to a considerable degree fit clearance between various parts have increased and sealing property of its gas valve has deteriorated resulting in an decrease in its actual gas discharge capacity Methods of Judgment Measure the high and low pressures with pressure gauges to see whether they are normal If an abnormal sound comes
13. Too much refrigerant charged into the system Analysis of Trouble a Incase the amount of refrigerant charged into the system exceeds its nominal capacity the superfluous refrigerant will of course take some space of the evaporator thus reducing its heat dissipation area and hence the refrigerating efficiency of the system The abnormal phenomena caused by this reason are as follows the gas suction and exhaust pressures are generally higher than their respective normal values the temperature of its condenser is higher and the electric current of the compressor rises loose frost forms on the evaporator the Freezer temperature drops slowly and frost appears on the gas return tube b In case excessive refrigerant has been charged the liquid refrigerant that cannot evaporates in the evaporator will return to the compressor and thus a phenomenon of liquid striking will occur The liquid refrigerant evaporates and effervesces as soon as it flows into the refrigerating oil at the bottom of compressor If the condition is severe foams will fill all over inside the compressor housing and be sucked by the piston causing damage to the components of compressor Hemedy According to the operating procedures it is mandatory to turn the achine off and several minutes later open the refrigerant charging tube and et the refrigerant escape from it replace the dry filter recharge refrigerant after evacuating and then seal the charging port 3
14. e evaporator The difference between the both is as follows if the clogging is 21 Maintenance Service and Trouble Shooting caused by dirt tapping the suspicious clogged point generally in the capillary or the connection joint of the filter may cause the refrigerant to flow through partially resulting in some corresponding change whereas in that case if you heat it with a hot towel no reaction will happen no flowing sound can be heard moreover there is no periodic change After rejecting the possibility of ice clogging it can be generally considered as the clogging due to dirt Remedy Dismantle the system remove the dry filter from it purge the tubing with nitrogen install a new filter then evacuate it and finally charge it with refrigerant C Clogging in filter Analysis of Trouble Total clogging of a filter is rarely to occur This trouble is mostly caused by the paste like matter formed from the substances filled into the system or other dust after the Freezer has been used for a longer time or by the dirt accumulated gradually inside the filter Sometimes tapping the filter nay cause a passage for flowing Touching it with your hand you will feel that it is cooler compared with its temperature in the normal state Hemedy The same as described in the capillary clogging with dirt 3 Troubles of Compressor a Breakage of gas suction and discharge valve blocks Analysis of Trouble The compressor works by means of
15. e Freezer immediately then check the insulation of electric circuits with an avometer b Serious electric leakage Never touch the case body of the Freezer its door handle or other metal parts with your hand Test the Freezer with a test pencil it will light up intensively measure the resistance between the power cord plug and the case body with an avometer the reading will be zero 0 in the worst case the fuse will be blown Check the 3 prong outlet to see whether the live wire and the null line are inversely connected this makes the ground protection lead out from the power cord plug being connected to the live wire Another possibility is that the live wire and null line of the outdoor power supply circuit have been inversely connected accordingly this makes the null line become a live wire G Stronger vibration and loader noise 1 Freezer placed improperly a Uneven ground Uneven ground will cause there frigerator to be placed unsteadily causing stronger vibration and noise during its operation b Leveling screws not properly adjusted If the leveling screws on Freezer legs have not been adjusted properly vibration and noise will still occur even if the Freezer has been placed on a level ground 2 Abnormal noise from compressor Three suspended spring inside the compressor case are out of balance and strike against the case moreover the wear of compressor parts may cause noise sometimes 3 Resonance of tubing and
16. e vicinity of the or microwaves on top of the chest freezer Do chest freezer to avoid fire not use electric app lances Expect thoes allowed by manufacturer inside the refrigerator Do notplayty hanging on iis door to Do notplace heavy or unstable articles or prevent tilting the door or topp ling the water containers on top of the refrigerator refrigerator to hurt person Safety precautions When the chest freezer has started running Do not spray water onto the chest freezer or take care notto touch the cold surface of place it in wet area susceptible tobe the freezer compartment with hand splashed with water so as to avoid especially with wet hand Otherwise your influencing the electric insulation skinis liable tobe stuck on the cold surface performance of the appliance It is Strictly prohibited to privately dismantle Do notput the bottled beer or beverage in or change the appliance For the repair of the freezer compartment to prevent frost chest freezer it can be carried out by crack professional only At no power supply or when carrying out When the appliance is to be discarded cleaning it is required to pull out the power dismantle its door as wellas its door gasket plug and to wait at least minutes for to avoid accident occurred when a child switching on itagain to prevent damaging goes inside for playing its comp ressor by continuous starting Function Schedule e Energy efficienc
17. eard and the gas suction pressure assumes a state of vacuum Note that these phenomena will appear intermittently sometimes the Freezer works well and sometimes not well In order to determine whether it is clogged with ice heat the suspicious points with hot water to make ice melt and after a while if a gas flowing sound resulting from an abrupt gush is heard and the gas suction pressure rises as well it can be confirmed that the trouble is caused by ice clogging Hemedy If there is too much moisture in the refrigerating system it is advisable to release the refrigerant purge the tubing with nitrogen and then charge the system with the filtered refrigerant However the commonly adopted method is to connect a filter with moisture absorbers such as silica gel anhydrous calcium chloride to the refrigerating system so as to filter out the moisture from the system then replace the filter evacuate it again and finally charge the system with refrigerant b Clogged with dirt in capillary Analysis of Trouble The capillary inlet is a place where coarse grained dirt or refrigerant oil in the system will tend to settle down and clog it In case considerable dirt accumulates there the whole filter screen may be blocked totally making the refrigerant unable to go through Clogging with dirt exhibits the same symptoms as that with ice namely higher gas suction pressure lower temperature of discharged gas and no gas flowing sound from th
18. ective prescribed ranges thus making a pressure operated protective relay shut off the power to the compressor and stop it In the following we discuss mainly the reasons for causing excessively high gas discharge pressure and low suction pressure 1 Stoppage due to excessively high gas discharge pressure A Too much refrigerant charged into the system Analysis of Trouble The phenomenon such as loose frosting and poor refrigerating effect may occur if excessive refrigerant has been charged into the system ouperfluous refrigerant will occupy a certain space of the evaporator thus reduce its heat dissipating area and the phenomenon of liquid striking may occur too Meanwhile dew or frost condensation may occur on the gas return tube and the gas discharge pressure will obviously rise when it reaches the threshold value the protective relay will actuate and shut off the power supply to the compressor Hemedy Open the tubing re evacuate and then charge the system with a proper quantity of refrigerant b Airleft in the system Analysis of Trouble The residual air in the system will circulate together with the refrigerant in the system The major symptoms caused by this residual air is higher gas discharge pressure higher discharged gas temperature the gas discharge tubing is considerably hot when you feel it with your hand and poorer refrigerating effect Furthermore the gas discharge pressure will exceed its normal value when t
19. ere is no damage to the compressor parts and its operating current becomes low its gas suction pressure is high and discharge pressure is lower the gas discharge tube feels rather cold no sound of gas eruption from the liquid in the evaporator can be 20 Maintenance Service and Trouble Shooting heard and no will gush out of the process tube if you cut it open after shutdown Remedy Check the whole machine particularly those locations which are liable to leak After leak points have been found repair them or replace them with new parts according to specific circumstances then evacuate the system and finally charge refrigerant 2 Refrigerating system has been clogged a Clogged with Ice Analysis of Trouble The dryness treatment for the major parts in the refrigerating system has been performed improperly the effect of air purging for the whole system is not good or the water content in the refrigerant is out of standard all these will cause the expansion valve to be clogged with ice The symptom for this trouble are as follows the Freezer sometimes can refrigerate and sometimes cannot the Freezer compartment works normally at the beginning but after working for a certain period of time frosting begins at the clogged position evaporation temperature reaches below 0 C water will accumulate at the narrow part of the capillary and clog it gradually then frost begins to melt at the evaporator no gas flowing sound can be h
20. essor run continuously and hence very low temperature will be achieved in the Freezer The fault is generally due to the fact that the contacts of the thermostat cannot be released Remedy Dismantle the thermostat and make a through checkup if it is totally out of functioning replace it with a new one 3 evaporation temperature is too high in refrigerating system resulting in lower refrigerating capacity and hence continuous running of compressor Analysis of Trouble Leakage of refrigerant and clogging in a refrigerating system will directly affect its refrigerating capacity Due to the reduction in its refrigerating capacity the Freezer temperature cannot reach its rated value the thermostat won t work thus the compressor runs continuously When the evaporation temperature in the system is too high the temperature sensing agent in the temperature sensor is also hotter therefore the thermostat is unable to cut off the power supply to the compressor and stop it Hemedy If it has been found that the refrigerant in the system is insufficient in quantity recharge it with refrigerant In case clogging occurs disassemble the part where it is blocked If the evaporation temperature is too high settle this problem with an appropriate quantity of refrigerant 4 No stoppage of compressor due to damaged heat insulation layer inside case body and or door seal Analysis of Trouble When the heat insulation layer inside the case body deteriora
21. he compressor has run for a period not too long thus making the protective relay actuate and bring to a stoppage Hemedy Check up how the air has been left in the refrigerating system Generally there are two possibilities one is that the air has been sucked into the system when repairing due to carelessness or it has not been purged out totally when evacuating the system the other is that there are leak points at the low pressure end of the refrigerating system Leak points appear mostly in those low temperature parts or assemblies because the evaporation temperature is lower for such low temperature devices especially at the low pressure end it is easier for the air goes into the system Once it has been ascertained that air does exist in the system you have to open the tubing re evacuate it and then charge it with refrigerant 2 Stoppage due to electric troubles a Thermostat is out of control Analysis of Trouble In case the thermostat does not work in its good order or its 23 Maintenance Service and Trouble Shooting temperature sensor has not been installed properly frequent stoppage Is also likely to occur Remedy Try to adjust the temperature sensor s position until the compressor can be started and stopped normally If this cannot be achieved and the stoppage still occurs repeatedly it is most likely that the mechanical parts or contacts are out of order disassemble the thermostat make a thorough checkup and repai
22. ice and Trouble Shooting 6 Common Troubles in Freezers and Their Remedies Causes for troubles occurring in Freezers are closely related to the quality of components and workmanship in assembling by manufacturers as whether Freezers are properly used and maintained The parameters generally used to express the working conditions of a Freezer include the temperature inside the Freezer operation rate electric power consumption noise level and other functional indexes If any one of these parameters is beyond its permissible range this indicates that there is a fault or trouble in the Freezer During the whole service life of a Freezer the probability of troubles occurring within a union time is called its failure rate Making a comparison between the control circuit system of a Freezer and its refrigerating system we can find that the failure rate of the former is higher and that of the thermostat is the highest In troubleshooting the first thing you must do is to determine where the trouble comes from the control system or the refrigerating system There is general no trouble indicating instrument mounted on the dome stic Freezer locations and natures of troubles should be determined according to their respective features therefore experience in servicing is very important to troubleshooting Service technicians with rich experience can correctly locate them and take reasonable remedy measures based on their comprehensive analysis
23. mperature lower than that in normal conditions and for a severe clogging even dew condensation as frosting may appear Remedy Purge the tubing and after replacing the dry filter with a new one or clearing it thoroughly recharge the system with refrigerant and seal the charging port B No Refrigerating The phenomenon that the compressor runs normally but no frost or only a little frost appears on the evaporator and the Freezer temperature does not drop down is called no refrigerating There are many causes for this trouble and it is relatively complicated too In servicing special attention to finding direct causes for this phenomenon Three main potential causes for this trouble are analyzed below 1 All refrigerant in the system has leaked out Analysis of Trouble Leak points in the refrigerating system have not been found and repaired timely thus resulting in the total escape of refrigerant There are two kinds of leakage l slow leakage for instance when we want to use a Freezer that has been put out of quite a long time we find the leakage of refrigerant or in the course of its operation we have found that the Freezer is gradually becoming not so cold and finally no refrigerating cab be achieved ii fast leakage in that case all the refrigerant will escape swiftly due to abrupt rupture of system tubing oymptoms of total leakage of refrigerant are mainly asfollows the compressor can be started easily if th
24. nance Service and Trouble Shooting 2 The compressor doesn t stop Compressor doesn t stop Check and repair according to Does the Freezer the section of No cooling refrgerate Is cooling capacity NO Check and repair according to insufficient the section of Cooling capacity is insuffcient YES 1 The thermostat was set at the coldest position 2 The ambient temperature is very high or NO Adjust and instruct the Freezer is near by heat resource 3 The door was opened too many times or there are more fresh food inside consumer how to use NO Check and repair the main control panel Maintenance Service and Trouble Shooting 3 Cooling capacity is insufficient Cooling capacity is insufficient s the ambient YES temperature low than 16 C Check the therostat is correct Does the refrigerant leak siowly Adjust and instruct consumer how to use 12 Maintenance Service and Trouble Shooting 4 The compressor doesn t work The compressor doesn t work Does the refrigerated po NO Check the power NO Pu HUNE s source and power e when the door Is cord opened YES YES Is the ambient YES Check the therostat is temperature low than correct Adjust and instruct consumer how to use Does the control panel has 220V power output Check and repair the control panel Does the compressor has 22
25. owing 7 aspects 1 Leakage of refrigerant Analysis of Trouble The leakage of refrigerant in the system will result in an insufficient refrigerating capacity the resulting phenomena are its lower gas suction pressure and exhaust pressure as well as higher exhaust gas temperature The exhaust tube feels rather hot and a continuous gas flowing sound louder than usual can be heard at the outlet of the capillary and no frost or a smaller quantity of loose frost appears on the evaporator After shut down the balance pressure in the system is usually lower than the saturation pressure corresponding to the same ambient temperature Hemedy In case there is leakage of refrigerant from the system do not hurry to recharge it with refrigerant manage to find out leak points immediately and make a note of from where it leaks welding points and parts After having them repaired recharge refrigerant Maintenance Service and Trouble Shooting There are so Many joints and sealed surfaces ina Freezer accordingly quite a lot potential leak points do exist in the system In troubleshooting pay attention to those parts that are liable to leak check main connection points for oil seepage and tubing for cracks lf there is no severer leak point charge the system with nitrogen and detect leak points with the commonly adopted method repair them evacuate charge the system with refrigerant and then turn on the Freezer to make a test run 2
26. r it b Overload of electric motor Analysis of Trouble Probably too many things have been put into the Freezer and hence the thermal load exceeds its refrigerating capacity or in case the power supply voltage drops considerably the current flowing through the motor will increase drastically making the thermal protector actuate and the fuse blown and hence the motor stops running If the motor is still running continuously in such a case its windings will be burned out Hemedy Reduce the thermal load pay attention to the variation in voltage of the power supply c Abnormal thermal protection Analysis of Trouble The compressor current is within its normal range but the thermal protector actuates repeatedly Hemedy Replace the thermal protector with a new one 3 Sudden stoppage due to other causes Normal Stoppage otart and stop of the compressor is generally controlled by a thermostat When the temperature in the Freezer reaches its desired value the thermostat will shut down the compressor automatically Never take this normal operation as a trouble care should be taken to differentiate it from other real troubles in servicing D Compressor won t start In case the compressor cannot be started you must find out the origins of this trouble through checkup step by step because probably there are many causes including those electrical and mechanical 1 Inspect the power supply to see whether it is connected to the
27. rcuited and measure the resistance of each phase with an 25 Maintenance Service and Trouble Shooting avometer If short circuit occurs or the resistance of a certain phase is low this means that short circuit does exist in the windings and or between turns and insulation layers have been burned or deteriorated A megameter can be used in this inspection too f the insulation resistance is lower than 2 MO this means that the insulation layer is already breakdown If the motor has been burned repair it or replaced it with a new one b Fault of control relay Analysis of Trouble Overheat burnout or wear of control relay contacts may occur generally All these will cause poor contact in electricity Hemedy Dismantle it to repair or replace it with a new one C Poor electric contactor in thermostat Analysis of Trouble Burnout of contactor and leakage of temperature sensing agent may occur generally Hemedy Replace the old with a new one d Check the terminals for loose connection and electric circuits for other abnormal phenomena 5 Mechanical faults of compressor a Seizing of shaft This phenomenon is caused mostly by poor lubrication such ad insufficient quantity of lubricant clogging in the lubricant oil line or intermittent lubricant oil supply Dirt and other impurities in the lubricant oil will increase its viscosity and cause the shaft to be seized Copper plating may also result in seizing of shaft b Sei
28. s just stopped running the refrigerant will flow for a certain time therefore this sound is a normal phenomenon 2 A click sound can often be heard from the Freezer This is a normal sound produced by the pull in or release of the armature of a current deadweight start relay when starting the compressor The compressor motor will produce a slight and uniform sound while it is running This sound is not easy to be heard in the daytime but of course it can be heard distinctly at night 3 he compressor consists of an electric motor and a compressing apparatus During its normal operatio the motor s stator core and windings will rise to a temperature in the range of 100 C 110 C and the temperature of the piston and cylinder of the compressing mechanism can also reach as above 100 C due to the heat produced when compressing refrigerant Most of the heat radiates to the air through the compressor casing therefore its casing is generally at a temperature between 85 C 90 C it is very hot particularly in summer when the ambient temperature is higher All these are normal phenomena 4 For the direct cooling Freezer a kind of irregular crack sound can be often heard when the compressor is running for a certain period of time or has just stopped its running This sound is caused by the stress relief due to expansion and contraction when temperature changes and will not affect the normal application of Freezer 14 Maintenance Serv
29. tes or the door seal is not closely touches the door frame the temperature in the Freezer will rise and makes the compressor running continuously Hemedy Check the heat insulation layer for its damaged parts repair it to improve its heat insulation property If the door has deformed or the door seal is not tightly sealed against the case body repair them respectively 5 Too much food is placed in the Freezer or is placed too densely resulting in poor ventilation or poor conditions for temperature sensing and hence no stoppage of the compressor 6 Too high ambient temperature poorer ventilation and heat 2 Maintenance Service and Trouble Shooting dissipation make the compressor running without stop F Electric leakage of Freezer 1 Slight electric leakage Electric insulation has deteriorated due to being affected with damp thus resulting in slight electric leakage 2 Serious electric leakage Freezer case has become live due to faults occurred in some electric devices or the erroneous wiring in installing power cord plug or outlet by the user This is very dangerous 3 Electric leakage test a Slight electric leakage A tingle sense will be experienced as soon as you touch the metal parts of the Freezer with your hand When you test them with a test pencil its neon lamp will come on In that case the first thing you need to do is to determine whether the grounding is perfect lf the grounding is no problem turn off th
30. ting effect Hemedy It is quite difficult to determine whether this trouble is caused by the refrigerating oil left in the evaporator tubing because this kind of phenomenon and other several trouble are tends to be confused Generally speaking you can make a judgment based on the frost formed on the evaporator If the frost does not cover the evaporator and moreover it is loosely formed you can make a judgment that the deterioration of 19 Maintenance Service and Trouble Shooting refrigerating effect is due to the accumulation of refrigerating oil left in the evaporator tubing in case no other troubles have been found To clear off refrigerating oil left in the evaporator dismantle the evaporator purge it thoroughly and then dry it In case it is difficult to dismantle it charge refrigerant from the evaporator inlet to wash it several times then purge and dry it with nitrogen 7 Flowing obstructed in refrigerating system Analysis of Trouble Because the refrigerating system was originally not purged thoroughly some of the filter screen meshes have been clogged by dirt accumulated in the filter after using it for a certain time of period thus resulting in a decrease in flow rate and hence a poorer refrigerating effect The abnormal phenomena caused by this kind of slight clogging in the system are as follows the gas discharge pressure is lower the temperature of discharged gas drops down the position clogged has a te
31. ting system the exhaust gas should be very hot and this is the normal working state For those Freezer with enclosed type of compressor refrigerating system no frost or dew drop will from on the gas suction tube otherwise there is something wrong in the system Frosting and dew condensation may appear for a very short time period when just starting the machine this is a normal phenomenon Because a Freezer is a combination of several components they are related and have influence on each other In case an abnormal phenomenon has been found through the above mentioned checkups you need not to make a hasty conclusion based on only one abnormal phenomenon It is advisable to find out two or more abnormal phenomenon or conduct troubleshooting comprehensively with the aid of instruments or other ways because several kinds of troubles may share a common abnormal phenomenon and two or more abnormal phenomena may occur simultaneously due to a certain trouble With this method you can reject some suspicious troubles and finally make a correct judgment 7 Analysis of Troubles and Troubleshooting A Poor Refrigerating Effect The so called poor refrigerating effect refers to the fact that the Freezer can operate and Freezer normally but the temperature in the Freezer cannot drop to the prescribed value under the stipulated working conditions In view of there are many causes for this phenomenon we are going to discuss and analyze it in the foll
32. y E Micro foam technology e Low noise operation e Thick insulation for energy efficiency Function Schedule System Flow Chart System Flow Chart 1 Schematic diagram of System Flow Chart 1 Compressor 2 Condenser 3 Dry Filter 4 Capillary Tube 9 Evaporator 2 Brief Description of System Flow Chart It isadirect cooling single system Freezer When the Freezer is just powered on the refrigerant flows in the sequence 1 gt 2 gt 3 gt 4 gt 5 gt 1 Circuit Diagram Circuit Diagram 1 Schematic Circuit Diagram see the rating label on the Freezer Brief Description of Control Principle It is a direct cooling single system Freezer with a small ice box a mechanical type of all the control is generally adopted The thermostat directly controls the start and stop of compressor and hence the Freezer temperature Maintenance Service and Trouble Shooting Maintenance Service and Trouble Shooting 1 No cooling No cooling If compressor can run after it stop to run five minutes and give power Check and repair according to the section of the compessor doesn t work If compressor Refrigerant can run naturally and leak check and temperature raising repair charge of condenser is refrigerant again very low When charging refrigerant we must Block by ice or dirty ging b notice to make refrigerant true things change filter and change refrigerant again 10 Mainte
33. zing of piston This is caused by too small fit clearance between the piston and cylinder or expansion due to heat Judgement of seizing shaft and piston After the Freezer has been powered on the compressor will not start and run but a slight hum sound can be heard and several seconds later thermal protective relay will actuate and make the contacts open this process will occur repeatealy but the compressor cannot be started E Compressor won t stop Sometimes the compressor will run continuously for several hours or run without end If the food placed in the Freezer is not too much there may be the following two situations i the Freezer very low this means that the control system is probably out of order ii the control system works normally and there are troubles in the refrigerating system or other parts 1 Temperature is set improperly a The temperature control knob is set to the coldest position This 26 Maintenance Service and Trouble Shooting position is to be used for fast freezing or continuous running Its temperature for power off is too low therefore the compressor won t stop and the temperature in the Freezer becomes lower and lower b Inspection method check the temperature control knob to see whether it is set in the position coldest 2 Thermostat is malfunctioning and makes the compressor running continuously Analysis of Trouble When the thermostat doesn t work normally it will make the compr
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